Among your options, it might be tempting to choose “unreliable”; however, the closest meaning for “erratic” is “irregular” or unpredictable. The word comes originally from the Latin meaning to stray or wander. When someone “errs,” he or she might make a mistake, but the strict sense is that person “goes the wrong way.” Someone might be “unreliable” because they are erratic; however, that is only because that person is irregular or unpredictable. Because they are so, they are thus unreliable.

The word “prolific” comes from the Latin for “bearing offspring.” When an animal is “prolific” it bears much fruit or many children. When an artist is prolific, he or she produces many works. An example sentence would be, “The old man had been a prolific author during his lifetime, writing over a hundred best-selling thriller novels.”

Originally used to describe beverages lacking in flavor, "vapid" came to describe anything that is dull or insipid.

When something is banal, it is extremely overused and has little meaning because of that. For instance, one might speak of a “banal phrase” that is really nothing but empty words or “banal song lyrics” that really express no meaning at all. When something is “vapid,” it does not stimulate at all. The word “vapid” comes from the Latin for “flat” or “tasteless.”

“Fruitful” means fertile, plentiful, fecund, or producing a lot of something, so "fecund," meaning fertile, is the correct answer. As for the other answer choices, “innocuous” means harmless; "blighted" means diseased and specifically refers to plants; "amiable" means friendly and warm in demeanor; and "growing" means maturing.

When used as a noun, "pedestrian" means "a person walking along a road or in a developed area." When used as an adjective, however, "pedestrian" means "lacking inspiration or excitement; dull." "Thrilling" cannot be the correct answer because "thrilling" is an antonym of "vim," and while "languid" may seem close in meaning to "pedestrian," "languid" means "displaying or having a disinclination for physical exertion or effort; slow and relaxed" when describing a person, manner, or gesture, "pleasantly lazy and peaceful" when describing an occasion or period of time, or "weak or faint from illness or fatigue." "Uneventful," an adjective that means "not marked by interesting or exciting events," is the closest synonym to "pedestrian" amongst the listed answer choices, so "uneventful" is the correct answer.

If a high school offers a myriad of classes, it means that there is a vast amount or a seemingly innumerable number of classes.

The word “myriad” is derived from the Greek for "10,000." In general, it is used to describe a countless multitude of things. For that reason, the best option among the provided answers is “innumerable.” An example usage would be, “Roger wished to do something so foolish that his friends were able to provide him with myriad reasons, overwhelming him with reasons for making such a stupid choice.”

You might be more familiar with the word “platitude” than with “platitudinous.” The former is the related noun form of the same base. A “platitude” is an expression, often moral in nature, that has been so overused that it has lost its meaning. You might know someone who recites such expressions as, “Everything happens for a reason.” Such remarks either tell you nothing or often just frustrate you when horrible things happen. They provide little consolation or direction. Although a “platitudinous” expression could be called “annoying,” it is most properly said to be something “overused.” The annoyance follows on the fact that overuse has totally shorn it of its meaning and significance.

"Replete" and "abounding" both mean full or well-stocked. "Scant" means meager or paltry. "Disingenuous" means insincere or deceitful. "Evanescent" means transient or brief. "Pugnacious" means belligerent or aggressive.